Dealing with Chernobyl's genetic legacy

Aworkshop held at the 9th International Congress of Human Genetics in Rio de Janeiro, Brazil last month, gave international experts the opportunity to examine the Chernobyl nuclear disaster from teratology and medical genetics perspectives. The workshop was organised by the University of South Alabama, USA (W Wertelecki) and the Medical University of South Carolina, USA (C Salinas). L Anspaugh (Lawrence Livermore National Laboratory, Livermore, USA), speaking on behalf of Ukrainian, Russian, and Byelorussion colleagues, reported that the collective effective dose to the liquidators, evacuees, and persons living in the contaminated areas was about 100 000 person-Sv during the 10 years after the accident—the genetically significant dose is about half that. In childhood-thyroid cancer, Anspaugh said, the increased incidence has been much larger than expected and has occurred much earlier than expected. Furthermore, many of the children with thyroid cancer had had relatively low thyroid doses of 0·1 Gy or less. A rough estimate of the collective dose to the thyroids in the affected areas in the three countries is 10 person (thyroid)-Gy. From a review of cytogenetic studies, primarily of Chernobyl clean-up workers, J R Lazutka (Vilnius University, Lithuania) noted that a study of chromosomal rearrangements may contribute to a better understanding of carcinogenesis. Some participants expressed concern that substantial cytogenetic studies remain unpublished, particularly those of children. The growing gap between decreased birth rates and increased death rates in Ukraine and Belarus were alluded to by I R Baryliak, G I Lazjuk, and L I Tegako (Centre of Hygiene, Kiev, Ukraine; Institute for Heredity Diseases and Anthropology-Ecology, Academy of Sciences, Minsk, Belarus). The birth-rate in Belarus is 30% below that of 3 years ago. In a paper submitted by J Neel (University of Michigan Medical School, Ann Arbor, USA), the world-renowned radiation geneticist who pioneered many studies of the Hiroshima-Nagasaki bomb survivors and their children said that “if we had to do such studies over again, the most obvious change in the research design would be to include studies at the DNA level from the outset”.